1. Department of Pharmacology and Pharmacognosy, School of Pharmacy and Health Sciences, United States International University-Africa, Nairobi, Kenya
2. Department of Pharmacology and Pharmacognosy, College of Health Sciences, University of Nairobi, Nairobi, Kenya
3. Department of Chemistry, University of Nairobi, Nairobi, Kenya
4. Centre for Virus Research, Kenya Medical Research Institute, Nairobi, Kenya
5. Royal Botanic Gardens, Richmond, Surrey, UK